Vulnerability · Published Feb 24, 2026 · Assigned by mozilla

CVE-2026-2634Spoofed web content presented under trusted domains using scripted navigation on Firefox iOS

Critical 9.8

In plain English

A critical-severity security flaw in Firefox for iOS from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.4%top 70.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Malicious scripts could cause desynchronization between the address bar and web content before a response is received in Firefox iOS, allowing attacker-controlled pages to be presented under spoofed domains. This vulnerability was fixed in Firefox for iOS 147.4.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-2634
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-2634
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2026-2634
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2026-2634
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2026-2634

Affected products (as reported)

VendorProductVersions
Mozilla Firefox for iOS see references

Weakness: CWE-451 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References